There is some inconsistency about Edna's origins. Though she is said to have come to Springfield to begin teaching in "The Seemingly Never-Ending Story," she can be seen running through the background in Springfield High School in "Springfield Up" when Clancy Wiggum is being videotaped as a hall monitor. Krabappel smokes heavily, especially during school hours. In the episode "Bart Gets a 'Z'", she is fired from teaching after getting drunk (Bart spiked her coffee) and decides to open a muffin store. She is later rehired when the substitute teacher got drunk.

Love life

A recurring theme is Ms. Krabappel's loneliness and longing for male company. She is divorced; in "Separate Vocations", she implies indirectly that her husband ran off with their marriage counselor. In early episodes, she is shown as very sexually aggressive and promiscuous: in "Flaming Moe's", she is shown with her arms around two sailors in the parody of the famous Cheers theme, and tries to pick up both Joey Kramer (Aerosmith's drummer) and Homer Simpson, even after learning he is married and Bart's father. In "Bart's Friend Falls in Love", while the children are watching the Sex Ed movie, she says to the children in disgust, "She's faking it". Also, when asked by Nelson Muntz about why she doesn't live with "Mr. Krabappel" in the same episode, she tells him that he "chased something small and fluffy down the rabbit hole". In "One Fish, Two Fish, Blowfish, Blue Fish" she has a "hot encounter" with a Japanesesushi chef on the backseat of her car. The episode "Bart the Lover" was the first episode to give Krabappel a central role, and also to expand her character and personality. Krabappel appears to be desired by many men, as seen in Sideshow Bob's outrage (in "Brother from Another Series") wherein his romantic date with her is ruined by a spying Bart: "You only get one chance with Edna Krabappel!"